Tokyo: Two Chinese patrol ships entered Japan's territorial waters off the Senkaku Islands in the East China Sea, the media reported.
Japan Coast Guard officials spotted the Chinese boats off the island of Uotsuri on Sunday afternoon, public broadcaster NHK reported.
The ships left Japan's territorial waters after staying in the area for about two hours.
This is the first intrusion by Chinese patrol ships into Japan's territorial waters off the Senkaku Islands since December 11.
It is also the 34th day this year that Chinese vessels have entered waters in the area.
Japan controls the Senkaku Islands. The Japanese government maintains that the islands are an inherent part of Japan's territory. China and Taiwan claim them.